六种城市绿地内夏季空气负离子与颗粒物

Air-borne anions and particulate matter in six urban green spaces during the summer

为合理规划城市绿地、有益于人们户外活动,研究了6种类型城市绿地空气负离子和颗粒物浓度的日变化、空气质量的差异,分析了负离子与不同粒径颗粒物之间的关系。结果表明:空气负离子和颗粒物浓度日变化均较明显;不同类型绿地空气负离子浓度存在显著差异,其浓度从大到小的顺序为阔叶乔草、乔灌草、阔叶乔木、篱草、针叶乔草、草坪;不同类型绿地空气颗粒物浓度没有显著差异。由枝叶茂盛的高大乔木组成的林地,其空气负离子水平和空气质量较好。总体上空气负离子与颗粒物的相关关系不显著,相比之下,空气负离子对细颗粒物的中和能力较强。

Air-borne anions, particulate matter concentrations and air quality were analyzed during the summer in six urban green spaces to evaluate the effect of urban green spaces and then effect on outdoor human activity. The results show that the anion and particulate matter concentrations varys markedly with time and the anion concentrations differ significantly among the six green spaces. The anion concentrations decreased from high to low in the deciduous tree-herb, arbor-shrub-herb, deciduous tree, greenbelt -herb, evergreen tree-herb, and herb. The Particulate matter concentration did not significantly differ among the 6 green spaces. The anion concentration was higher and the air quality was better in forests dominated by trees than by other vegetations. The anions effectivety neutralize PM2.5 particulates.